Laws of Kashrus

The Almighty gifted us the laws of what is Kosher for us to grow spiritually. Since G-d’s wisdom is Divine our adherence to the laws of Kosher is what brings a Jewish person closer to G-d. It is this wisdom that allows us to discern between the sacred and the profane, the good and the bad. Kosher food takes the mundane and raises to a level of holiness which in turn feeds our souls.

The laws of kashrus are to be found first and foremost in the written Torah (Bible) and then supported by the Oral Torah (Talmud, Mishnah, Gemara) in which the sages carefully studied every detail of kosher and looked at every angle and opinion in order to establish a system by which Jews worldwide could adhere to the laws of Kosher and confirm the laws of kosher in regards to food preparation and commercial production.

Please read below to see explanations of some of the more pertinent laws of Kosher as it relates to kosher certification:

Basar – Meat

Kosher Animals

Leviticus 11:4-8, Deuteronomy 14:7,8. The text in Leviticus states, “But this is what you shall not eat from among those that bring up their cud or that have split hooves: the camel, for it brings up its cud, but its hoof is not split – it is unclean to you; and the hyrax, for it brings up its cud, but its hoof is not split – it is unclean to you; and the hare, for it brings up its cud, but its hoof is not split – it is unclean to you; and the pig, for its hoof is split and its hoof is completely separated, but it does not chew its cud – is unclean to you. You shall not eat of their flesh nor shall you touch their carcass – they are unclean to you.”


Poultry – birds can not be specifically identified as kosher by any defining characteristic. Rather the torah gives a list of 24 species of birds which are NOT kosher and through tradition and minhag (community custom) other species are accepted as kosher.

Leviticus 11:13-19, Deuteronomy 14:12-18. The text in Leviticus states, “These shall you abominate from among the birds, they may not be eaten – they are an abomination: the nesher, the peres, the ozniah; the daah and the ayah according to its kind; every orev according to its kind; the bas hayaanah, the tachmos, the shachaf, and the netz according to its kind; the kos, the shalach, and the yanshuf; the tinshemes, the kaas, and the racham; the chasidah, the anafah according to its kind, the duchifas, and the atalef.”

Jews are precluded from eating the limbs of an animal taken while it was alive and from “gid hanashe,” or the eating of the sciatic nerve of an approved kosher animal.

Shechitah – the slaughter of animals according to Jewish law

The Torah hands down clear cut laws pertaining to the ritual and proper slaughter of animals which will inflict the least amount of pain, ( tzaar baalei chaim (inflicting pain upon living creatures) and be the most humane in manner. Proper Shechitah requires that the neck of a kosher animal be cut with an extremely sharp knife in a specified manner in one continuous act. Anything to the contrary renders the slaughter as ‘treif’ “treifah” is defined as torn, (or not acceptable and thus not kosher for consumption, even when done to a known and otherwise kosher animal. In addition to an animal becoming treifah due to improper slaughter the prescence of certain lesions, lacerations, broken limbs, missing or punctured organs, or the result of an attack by a larger animal can also render it unkosher.

Of utmost importance is the inspection of the lungs of an animal, on which adhesions, called “sirchot,” may develop. Their presence usually means a performation or hole in the lung is present and this renders the animal unfit. Generally speaking this occurs only with meat and not poultry. You may hear the term Glatt, which is Yiddish ( a mixture of Hebrew and German spoken by Eastern European Jews) which means ‘Smooth’ and which denotes the absence of any kind of lesion or problem in the lungs.

Even more strict standards are held by Sephardic Jews who follow the dietary laws of “Beis Yosef Shechitah,” as written down by Rabbi Yoseph Karo.

Once an animal is shected, it still must be drained of all of its blood and salted in order to soak up any remaining blood before it can be called as kosher. Blood is considered as a life force and Jews are strictly forbidden to drink the blood of any animal.

Cheilev – prohibited fats

Nikur is the skilled action taken by an expert in Kashrus and Shechitah who knows the proper identification of forbidden fats and how to safely remove them from sheep, goats, and cattle.

Leviticus 7:23-25: “Speak to the children of Israel, saying: Any fat of oxen, sheep, or goats – you shall not eat. The fat of an animal that died and the fat of an animal that had been torn to death may be put to any use; but you shall not eat it. For anyone who eats the fat of animal species from which one may bring a fire-offering to G-d – the soul that eats will be cut off from its people.”

Cholov – Dairy:

Milk - cows’ milk and goats’ milk are kosher as are butter, cream cheese, ice cream, and other products that are derived from the milk of kosher animals, but, only if no non-kosher ingredients are also present.

“cholov yisrael,” literally the milk of an Israelite (a Jew). This is milk and any milk derived product which was “watched” by a Jew from the time of milking straight through until the time of ingestion. This is to safeguard the introduction of milk from a non-kosher animal mixed in with the milk of a kosher animal.

For many Jews, accepting the ruling by Rabbi Feinstein, who wrote that government inspection is a valid substitute for Jewish supervision, milk is considered kosher so long as it is from a kosher animal. This is termed Cholov Stam.


Parve is a designation of a food stuff being neither milk nor meat. It is neutral. Fruits and Vegetables as well as Fish and even Eggs are considered to be Parve.

Fish – all kosher species of fish must have both fins and scales which are clearly visible even if the scales fall off when the fish is removed from the water. Those fish species in which later in life they have scales are also permitted.

Fruits and vegetables and the consumption of insects

In general all fruits and vegetables are kosher in their raw sense. Only pairing non-kosher food items with them would render them unkosher. However, there is the concern of eating insects, which the Torah specifically prohibits, and which are present in produce. This requires “bedikah,” checking or searching. These foods must be checked for “shratzim,” swarming insects. This requires thorough examination and washing to remove creeping creatures which are forbidden.

Swimming insects - Leviticus 11:10-11
Flying insects – Leviticus 11:23
Creeping insects – Leviticus 11:29-31,41-43: “

Now in addition to the approved and forbidden foods there are several circumstances which arise which must be carefully adhered to in order to maintain stringent kosher standards:

“basar b’cholov”

“meat with milk,” – the torah specifically states “You shall not cook a kid in the milk of its mother.” This includes the following three circumstances:

1) the prohibition of eating the combination;
2) the prohibition of benefiting from the combination;
3) the prohibition of cooking the combination.

“kilayim.” – mixing of various species of plants is forbidden:

one may not plant vegetables or grains near one another - “kilaei zeraim.” Nor should they be mixed with grape vines “kilaei hakerem.” To do otherwise would be to negate the belief that G-d created the world and all that is in it perfectly and the mixing of species would attempt to negate that belief.

Leviticus 19:19. The verse actually discusses three types of forbidden mixtures: “You shall observe my decrees; you shall not mate your animal into another species, you shall not plant your field with mixed seed; and a garment that is a mixture of combined fibers shall not come upon you.”

This prohibition goes to far as to prohibit the wearing of garments which combine linen and wool for example whose fibers would be intertwined in violation of the mixing of plant species. This is called Shatnitz.

"mixtures" (hilkhot taarovot). These laws address questions concerning contact between kosher and non-kosher food

"YAVESH BE-YAVESH," literally, a mixture of dry substances.

"LACH BE-LACH," literally, a "wet mixture." In this scenario, the non-kosher substance melds with the kosher substance, and cannot be separated. This can occur when two liquids, kosher and non-kosher, are mixed together.

MIN BE-SHEINO MINO (dissimilar) mixture

"giulei nakhrim, the taste of non-kosher food expelled from the cooking utensils, may prohibit any food subsequently cooked within them.

Please note that these are just a few of the pertinent laws of kashrus or dietary laws which are provided for a general understanding of kosher and the specific laws which pertain to a particular production processes will need to be reviewed by the Mashgiach or kosher inspector.